Jiannan Yao1, Manyu Li1, Huiyun Zhang1, Yang Ge1, Nathaniel Weygant2, Guangyu An3. 1. Department of Oncology, Beijing Chao-Yang Hospital, Capital Medical University, Beijing 100020, China. 2. Academy of Integrative Medicine, Fujian University of Traditional Chinese Medicine, Fuzhou 350122, China; Fujian Key Laboratory of Integrative Medicine in Geriatrics, Fuzhou 350122, China. Electronic address: nweygant@gmail.com. 3. Department of Oncology, Beijing Chao-Yang Hospital, Capital Medical University, Beijing 100020, China. Electronic address: agybjcy@163.com.
Abstract
BACKGROUND: Colitis is a life-threatening and common immune-related adverse event in patients receiving immune checkpoint inhibitors (ICIs). Therefore, we performed a meta-analysis to assess the risk of immune-related colitis among various ICI treatment regimens. METHODS: We used PubMed, EMBASE, and the Cochrane Library to retrieve phase II or III randomized controlled trials (RCTs) of ICIs that specified the number of all-grade (grade 1-5) colitis and high-grade (grade 3-5) colitis events through January 2020. The pooled relative risk (RR) and 95% confidence intervals (CIs) were calculated to compare the risk of colitis among various therapeutic regimens. RESULTS: The search strategy identified 40 RCTs involving 26,893 patients. The risk of all-grade and high-grade colitis after PD-1/PD-L1 inhibitor was significantly lower than that of CTLA-4 inhibitor (0.18 and 0.14 relative risk respectively). The risk of all-grade and high-grade colitis was dose-dependent for CTLA-4 inhibitor therapy, but not for PD-1/PD-L1 inhibitor therapy. The relative risk of all-grade and high-grade colitis after combination therapy with PD-1/PD-L1 inhibitor and CTLA-4 inhibitor compared to PD-1/PD-L1 inhibitor alone was 9.25 and 12.00 respectively. No significant difference was found between PD-1/PD-L1 inhibitor combined with chemotherapy or targeted therapy and PD-1/PD-L1 inhibitor alone for either all-grade or high-grade colitis. CONCLUSIONS: Our meta-analysis indicates that CTLA-4 inhibitor is associated with a higher risk of colitis compared with PD-1/PD-L1 inhibitor, whether used as a monotherapy or combination immunotherapy. Importantly, the combination of PD-1/PD-L1 inhibitor with chemotherapy or targeted therapy may not increase the risk of colitis significantly compared to PD-1/PD-L1 inhibitor alone.
BACKGROUND:Colitis is a life-threatening and common immune-related adverse event in patients receiving immune checkpoint inhibitors (ICIs). Therefore, we performed a meta-analysis to assess the risk of immune-related colitis among various ICI treatment regimens. METHODS: We used PubMed, EMBASE, and the Cochrane Library to retrieve phase II or III randomized controlled trials (RCTs) of ICIs that specified the number of all-grade (grade 1-5) colitis and high-grade (grade 3-5) colitis events through January 2020. The pooled relative risk (RR) and 95% confidence intervals (CIs) were calculated to compare the risk of colitis among various therapeutic regimens. RESULTS: The search strategy identified 40 RCTs involving 26,893 patients. The risk of all-grade and high-grade colitis after PD-1/PD-L1 inhibitor was significantly lower than that of CTLA-4 inhibitor (0.18 and 0.14 relative risk respectively). The risk of all-grade and high-grade colitis was dose-dependent for CTLA-4 inhibitor therapy, but not for PD-1/PD-L1 inhibitor therapy. The relative risk of all-grade and high-grade colitis after combination therapy with PD-1/PD-L1 inhibitor and CTLA-4 inhibitor compared to PD-1/PD-L1 inhibitor alone was 9.25 and 12.00 respectively. No significant difference was found between PD-1/PD-L1 inhibitor combined with chemotherapy or targeted therapy and PD-1/PD-L1 inhibitor alone for either all-grade or high-grade colitis. CONCLUSIONS: Our meta-analysis indicates that CTLA-4 inhibitor is associated with a higher risk of colitis compared with PD-1/PD-L1 inhibitor, whether used as a monotherapy or combination immunotherapy. Importantly, the combination of PD-1/PD-L1 inhibitor with chemotherapy or targeted therapy may not increase the risk of colitis significantly compared to PD-1/PD-L1 inhibitor alone.